Western Digital WD20EARS "Advanced Format" - 4k sectors needed

I just purchased a Western Digital WD20EARS which uses "Advanced Format" which to my understanding are 4k sectors rather than 512 byte sectors. To function properly, the partitions need to align with this 4k sector size - like an SSD? Anyway, I found the following references, but wanted to ask here too before I attempt partitioning the hdd: what is the proper process and software to ensure that I do this correctly?

* This post talks about using parted from the shell for the partitioning.* I've also read in various places to simply start the partition with fdisk in sector mode (hitting 'u') and be sure to start at sector 64 rather than on sector 63. Example. Example 2 (you have to search for the keyword 'linux')* I've also read to do the same, except to start at sector 2048.* This post at the centos forum recommends using 'fdisk -H 224 -S 56 /dev/sdX' to "make sure that all possible partitions will be in alignment with the 4K sectors. Any partition you create that way will align the partition with the 4K sectors."

Re: Western Digital WD20EARS "Advanced Format" - 4k sectors needed

I'm torn apart between worlds. Basically, using vim in a highly visual environment with a lot of mouse features feels like soldering a lose wire to a motherboard with a Zippo and a needle, while working with ANY TEXT AT ALL with a "modern GUI" text editor feels like joining the London Philharmonic Orchestra with a Fisher-Price Laugh and Learn Magical Musical Mirror. --Awebb

Re: Western Digital WD20EARS "Advanced Format" - 4k sectors needed

I just used fdisk (setting both modes 'c' and 'u') and aligned it to sector 2048 - interestingly, in sector mode, the default starting point is not 63 or 64 but 2048 in the current version of fdisk (2.17.2) so it's automatically taking care of the 4k sector size for me. Everything works fast so I'm assuming that it's correct.

Not too bad considering the WD20EARS spins ~18 % slower than the other two.

EDIT: This drive also attempts to part the read heads once every 8 seconds which is just horrible. Use hdparm in your /etc/rc.local to disable this 'feature' and likely add life to your hdd:

# echo "hdparm -S 242 /dev/sdX" > /etc/rc.local

EDIT2: Here is a trivial script that detects the presence of this drive on my system and automatically send that hdparm command. Note that I only have a WD20EARS and this script won't work for multiple copies.

Re: Western Digital WD20EARS "Advanced Format" - 4k sectors needed

EDIT: This drive also attempts to part the read heads once every 8 seconds which is just horrible. Use hdparm in your /etc/rc.local to disable this 'feature' and likely add life to your hdd:

# echo "hdparm -S 242 /dev/sdX" > /etc/rc.local

What exactly is the problem with this HDD's and is it recommend to use the hdparm tweak you posted ?

I have 2x WD20EARS 2TB as Software RAID0, 512KB stripe block and EXT4 on it with journal disabled. While overall performance seems fine i think there are problems with the access time, its sometimes lagging and movies stutter occasionally or games freeze when loading from the RAID. Using 4KB blocks would improve anything here ?

Re: Western Digital WD20EARS "Advanced Format" - 4k sectors needed

EDIT: This drive also attempts to part the read heads once every 8 seconds which is just horrible. Use hdparm in your /etc/rc.local to disable this 'feature' and likely add life to your hdd:

# echo "hdparm -S 242 /dev/sdX" > /etc/rc.local

What exactly is the problem with this HDD's and is it recommend to use the hdparm tweak you posted ?

I have 2x WD20EARS 2TB as Software RAID0, 512KB stripe block and EXT4 on it with journal disabled. While overall performance seems fine i think there are problems with the access time, its sometimes lagging and movies stutter occasionally or games freeze when loading from the RAID. Using 4KB blocks would improve anything here ?

Yeah, 4k blocks would improve efficiency - these are after all meant to be formatted as such ("Advanced Format"). The head parking is an entirely different issue. What does smartmontools say about your llc?

Re: Western Digital WD20EARS "Advanced Format" - 4k sectors needed

Hmm what's llc ? I only have the gnome disk utility installed at the moment but can do smartmontools later. So this HDD will go into standby mode after only 8 seconds idle time and hdparm -S 242 /dev/sdX will set it to go standby after 60 minutes idling ?

Re: Western Digital WD20EARS "Advanced Format" - 4k sectors needed

Basically, yes. LLC = typeo on my part... it should be LCC which stands for load cycle count. You can read it from your SMART chip in the HDD. gnome disk utility will display this I think. Each number is a count of when the read heads park. The HDD will park them once every 8 seconds.

Re: Western Digital WD20EARS "Advanced Format" - 4k sectors needed

You have a small spelling error in your wiki entry that should read, I think: "will attept to park the read heads" and not "will attempt to part the read heads."

Sorry to nitpick but it is a small error that may confuse those whose native language is not english.

Last edited by MoonSwan (2010-07-14 22:31:51)

I'm torn apart between worlds. Basically, using vim in a highly visual environment with a lot of mouse features feels like soldering a lose wire to a motherboard with a Zippo and a needle, while working with ANY TEXT AT ALL with a "modern GUI" text editor feels like joining the London Philharmonic Orchestra with a Fisher-Price Laugh and Learn Magical Musical Mirror. --Awebb

Re: Western Digital WD20EARS "Advanced Format" - 4k sectors needed

Thats for both of my WD20EARS.That would be about 2150 power on hours here, but much less than your value for LCC.PC is in normal use, running 8-10 hours a day. I'm planning to get another 2 of these HDD's and go RAID5 with 4 disks.

Regarding the hdparm tweaks, people on a german hardware shop's forum (mindfactory.de) claim the warranty is lost when manipulating these settings, i'm not sure if that's true or if WD can find out if you get in the unfortunate situation to send them in.

Re: Western Digital WD20EARS "Advanced Format" - 4k sectors needed

I dunno man, 117,080 is huge if you asked me. 54 times per hour. Mine is much lower than what I posted. I pasted that out of a thread from another forum. Anyway, I would recommend that you use that hdparm tweak.

Re: Western Digital WD20EARS "Advanced Format" - 4k sectors needed

graysky wrote:

I dunno man, 117,080 is huge if you asked me. 54 times per hour. Mine is much lower than what I posted. I pasted that out of a thread from another forum. Anyway, I would recommend that you use that hdparm tweak.

Hmm ok thanks i will use that then. I start to believe the permanent head parking is maybe the reason why i get occasional lag/stutter when loading from the raid, for example i play a game and it freezes for 1-2 seconds the moment its loading something during gameplay. I never had that with my old hdds, 2x samsung and raid0 as well.

Edit: I found your thread on anandtech through google search for the wd20ears park issue and further info on kerneltrap, they explicitly recommend to turn it off when using a sw-raid with mdadm. And the 10 more watts power consumption without head parking...who cares, if i want to save power i turn off my pc but while its on i expect things working reliable at maximum performance.

Re: Western Digital WD20EARS "Advanced Format" - 4k sectors needed

After adding

hdparm -S 242 /dev/sdbhdparm -S 242 /dev/sdc

to /etc/rc.local and using my pc the whole evening, this command does nothing to the load cycle count, its still the same as before. If i hit the Refresh button in the disk utility i can see how the value still happily raises every few seconds ><The -S 242 command is probably only for spin-down after one hour but does not affect the park timer, at least not here at the moment.

Edit: Its suggested to use hdparm -B 255 to disable the power saving modes but that command just gives error messages:

It looks like WD does not officially support this tool for WDXXEARS but many people recommend to do this.I used the /D option instead of /S300 (D is meant for disable but it set it to 62 minutes).HDD's have to be connected only one at time and in IDE mode, the tool didn't detect anything with disks in AHCI mode.Was quiet annoying and hopefully worth it, my load cycle count didn't raise anymore within the last ~45 minutes

Re: Western Digital WD20EARS "Advanced Format" - 4k sectors needed

Re: Western Digital WD20EARS "Advanced Format" - 4k sectors needed

I'm sorry to disappoint you but hdparm will probably report the same values regardless of partitions being aligned or not, the issue with 4K sector drives is writing not reading. However if fdisk suggested 2048 as the beginning of the first partition then I'd say things will be ok.

Re: Western Digital WD20EARS "Advanced Format" - 4k sectors needed

sorry to revive this, but graysky, is your WD20EARS still working over a year later? (I've seen some really negative reviews...)

Any society that would give up a little liberty to gain a little security will deserve neither and lose both.-Benjamin FranklinThe reasonable man adapts himself to the world; the unreasonable one persists in trying to adapt the world to himself. Therefore all progress depends on the unreasonable man.-George Bernard Shaw